1. Field of the Invention
The present invention relates to a rotational force transmission mechanism, a force-attenuating apparatus, a medical device, and a medical instrument-operation mechanism.
2. Background Art
Laparoscopic surgery is a conventionally known technique that has been employed when performing a medical procedure such as observation or treatment of the internal organs of the human body. Rather than making a large abdominal incision, laparoscopic surgery allows for the procedure to be carried out by making several openings in the abdominal wall, and inserting a laparoscope and surgical instruments such as forceps into these openings. This type of surgery offers the benefit of being less invasive on the patient, since only small openings are made in the abdominal wall.
As a method of even further reducing stress on the patient, it has been proposed in recent years to carry out medical procedures by inserting a flexible endoscope into the patient via a natural opening such as the mouth, nostrils or anus. An example of a medical treatment endoscope used in such procedures is disclosed in U.S. Patent Application Publication No. 2005/0065397.
In the medical treatment endoscope disclosed in this reference, arm members that have a bendable end are respectively inserted into a plurality of lumens disposed within a flexible inserted part that is inserted into the body via the mouth of the patient. By inserting respective instruments through these arm members, the procedure site of interest can be approached from different directions with the various instruments. Accordingly, a plurality of procedures can be carried out in continuum by means of a single endoscope inserted into the body.